One proposed soil skeleton analysis program is designed to enable three-dimensional soil deformation analysis or three-dimensional consolidation analysis (see, for example, Non-Patent Reference 1). Another proposed soil skeleton analysis program uses a mechanical constitutive model expressing static behaviors of a soil foundation (see, for example, Non-Patent Reference 2). These soil skeleton analysis programs are expected to accurately estimate the water permeability, the consolidation, the stress in the soil foundation, the shear, the earth pressure, and the slope stability.    Non-Patent Reference 1: brochure of ‘FEM analysis support system of soil structures AFIMEX-GT’, Fujitsu FIP Corporation, No. 0040708-2    Non-Patent Reference 2: homepage of ‘GeoFEM, Multi-Purpose/Multi-Physics Parallel Finite Element Simulator/Platform for Solid Earth’, Coastal Development Institute of Technology, searched on May 13, 2005.